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1.
FMRFamide-like immunoreactivity has been demonstrated in the digenean trematode Echinostoma liei. The functions of FMRFamide-like substances appear to be many and varied within the invertebrates, where they are involved in neurotransmission, cardiovascular regulation, muscular contraction and/or relaxation, and in co-ordination of growth and maturation. It is clearly indicated that FMRFamide-like substances function as neurotransmitter/neuromodulator in E. liei by the abundance of positively stained nerve fibres and perikarya seen throughout the CNS and PNS. A single endocrine-like cell also showing FMRFamide-like immunoreactivity is situated within the muscular cirrus pouch.  相似文献   
2.
The challenge in the artificial CO2 reduction to fuel is achieving high selective electrocatalysts. Here, a highly selective Cu2O/CuO heterostructure electrocatalyst is developed for CO2 electroreduction. The Cu2O/CuO nanowires modified by Ni nanoparticles exhibit superior catalytic performance with high faradic efficiency (95% for CO). Theoretical and experimental analyses show that the hybridization of Cu2O/CuO nanowires and Ni nanoparticles can not only adjust the d‐band center of electrocatalysts to enhance the intrinsic catalytic activity but also improve the adsorption of COOH* intermediates and suppress the hydrogen evolution reaction to promote the CO conversion efficiency during CO2 reduction reaction. An in situ Raman spectroscopic study further confirms the existence of COOH* species and the engineering intermediates adsorption. This work offers new insights for facile designing of nonprecious transition metal compound heterostructure for CO2 reduction reaction through adjusting the reaction pathway.  相似文献   
3.
BackgroundChagas disease, caused by the parasite Trypanosoma cruzi, is a neglected tropical disease that causes severe human health problems. To develop a new chemotherapeutic agent for the treatment of Chagas disease, we predicted a pharmacophore model for T. cruzi dihydroorotate dehydrogenase (TcDHODH) by fragment molecular orbital (FMO) calculation for orotate, oxonate, and 43 orotate derivatives.Conclusions/SignificanceFMO-based interaction energy analyses revealed a pharmacophore model for TcDHODH inhibitor. Hydrogen bond acceptor pharmacophores correspond to Lys43 and Lys214, hydrogen bond donor and acceptor pharmacophores correspond to Asn67 and Asn194, and the aromatic ring pharmacophore corresponds to FMN, which shows important characteristics of compounds that inhibit TcDHODH. In addition, the Lys214 residue is not conserved between TcDHODH and human DHODH. Our analysis suggests that these orotate derivatives should preferentially bind to TcDHODH, increasing their selectivity. Our results obtained by pharmacophore modeling provides insight into the structural requirements for the design of TcDHODH inhibitors and their development as new anti-Chagas drugs.  相似文献   
4.
The effect of 2‐(2‐nitrovinyl)furan on the redox status of male rat liver and kidney was evaluated. Twenty male rats were randomized into four groups; group A received olive oil and groups B, C, and D rats received 12.5, 25, and 50 mg/kg bodyweight of 2‐(2‐nitrovinyl)furan intraperitoneally, daily at 24 h interval, respectively, for 14 days. 2‐(2‐Nitrovinyl)furan significantly reduced (P < 0.05) alkaline phosphatase, alanine, and aspartate aminotransferase activities in male rat liver and kidney with a corresponding increase in serum. The activities of superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, and levels of reduced glutathione/glutathione disulfide (GSSG) ratio in the liver and kidney of 2‐(2‐nitrovinyl)furan‐treated rats decreased significantly (P < 0.05). In contrast, GSSG, protein carbonyl, conjugated dienes, lipid hydroperoxides, malondialdehyde, and fragmented DNA (%) in 2‐(2‐nitrovinyl)furan‐treated rats increased significantly (P < 0.05). Overall, data from this study revealed that 2‐(2‐nitrovinyl)furan exhibited its toxic effect by suppressing or depleting the antioxidant systems.  相似文献   
5.
A number of studies have described malaria parasitaemia in pregnancy as mostly an asymptomatic condition, however information about predictors of asymptomatic malaria is largely lacking. We investigated the prevalence of symptoms and potential predictors of asymptomatic malaria in pregnant women attending Ante-Natal Clinic (ANC) of two public maternity hospitals in Ibadan, Southwest-Nigeria. Demographic data, history of previous and present pregnancy were obtained from the subjects and blood smears were examined for malaria diagnosis by light microscopy. Seventy - seven parasitaemic pregnant women attending antenatal clinic were evaluated for presence or absence of symptoms that may be associated with malaria. Thirty-seven women (48%) were asymptomatic whereas 40 (52%) presented with symptoms such as weakness, headache and general body ache and fever. Parasite density was significantly higher in symptomatic patients (P = 0.042), while asymptomatic patients had low level parasitaemia but significantly higher gametocyte carriage (P = 0.035). In conclusion, parasitaemic pregnant women resident in hyper- or holo-endemic malaria region are likely to be symptomatic with increasing density of the parasitaemia.  相似文献   
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7.

Background

Whether inhaled corticosteroids suppress airway inflammation in chronic obstructive pulmonary disease (COPD) remains controversial. We sought to determine the effects of inhaled corticosteroids on sputum indices of inflammation in stable COPD.

Methods

We searched MEDLINE, EMBASE, CINAHL, and the Cochrane Databases for randomized, controlled clinical trials that used induced sputum to evaluate the effect of inhaled corticosteroids in stable COPD. For each chosen study, we calculated the mean differences in the concentrations of sputum cells before and after treatment in both intervention and control groups. These values were then converted into standardized mean differences to accommodate the differences in patient selection, clinical treatment, and biochemical procedures that were employed across original studies. If significant heterogeneity was present (p < 0.10), then a random effects model was used to pool the original data. In the absence of significant heterogeneity, a fixed effects model was used.

Results

We identified six original studies that met the inclusion criteria (N = 162 participants). In studies with higher cumulative dose (≥ 60 mg) or longer duration of therapy (≥ 6 weeks), inhaled corticosteroids were uniformly effective in reducing the total cell, neutrophil, and lymphocyte counts. In contrast, studies with lower cumulative dose (< 60 mg) or shorter duration of therapy (< 6 weeks) did not demonstrate a favorable effect of inhaled corticosteroids on these sputum indices.

Conclusions

Our study suggests that prolonged therapy with inhaled corticosteroids is effective in reducing airway inflammation in stable COPD.  相似文献   
8.
9.
Cell wall mycolic acids (MA) from Mycobacterium tuberculosis (M.tb) are CD1b presented antigens that can be used to detect antibodies as surrogate markers of active TB, even in HIV coinfected patients. The use of the complex mixtures of natural MA is complicated by an apparent antibody cross-reactivity with cholesterol. Here firstly we report three recombinant monoclonal scFv antibody fragments in the chicken germ-line antibody repertoire, which demonstrate the possibilities for cross-reactivity: the first recognized both cholesterol and mycolic acids, the second mycolic acids but not cholesterol, and the third cholesterol but not mycolic acids. Secondly, MA structure is experimentally interrogated to try to understand the cross-reactivity. Unique synthetic mycolic acids representative of the three main functional classes show varying antigenicity against human TB patient sera, depending on the functional groups present and on their stereochemistry. Oxygenated (methoxy- and keto-) mycolic acid was found to be more antigenic than alpha-mycolic acids. Synthetic methoxy-mycolic acids were the most antigenic, one containing a trans-cyclopropane apparently being somewhat more antigenic than the natural mixture. Trans-cyclopropane-containing keto- and hydroxy-mycolic acids were also found to be the most antigenic among each of these classes. However, none of the individual synthetic mycolic acids significantly and reproducibly distinguished the pooled serum of TB positive patients from that of TB negative patients better than the natural mixture of MA. This argues against the potential to improve the specificity of serodiagnosis of TB with a defined single synthetic mycolic acid antigen from this set, although sensitivity may be facilitated by using a synthetic methoxy-mycolic acid.  相似文献   
10.
To investigate the effects of the coexistence of aflatoxin B1 (AFB1) and protein malnutrition in rat liver, weanling rats were fed either normal protein diet (20% protein), low‐protein (PEM) diet (5%), normal protein diet + 40 ppb AFB1, or low‐protein diet + 40 ppb AFB1. After 8 weeks, biomarkers of hepatic functions and oxidative stress, caspase‐3 activity, and tumor suppressor protein 53 (p53) were determined spectrophotometrically. Randomly amplified polymorphic DNA polymerase chain reaction (RAPD‐PCR) was employed to determine genomic alterations among the groups. Coexistence of aflatoxicosis and PEM significantly decreased glutathione, glutathione‐S‐transferase, glutathione peroxidase, and superoxide dismutase, while it increased peroxidase and catalase. RAPD‐PCR showed genomic alterations that were associated with significant increases in p53 level and caspase‐3 activity in rats fed PEM diet + AFB1. In conclusion, the coexistence of aflatoxicosis and protein malnutrition induced oxidative stress with concomitant genomic alterations in the liver of weanling rats.  相似文献   
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